i am using gravity forms version 1.4.5 and gravity forms salesforce add-ons 1.1.1. but after installation. i am not getting the option "Enable Salesforce integration" in Advanced" tab of Form Settings, even salesforce option is not comming in form(dashboard left side menu).i updated the gravity form version by clicking Forms>updates from dashboard.
http://wordpress.org/extend/plugins/gravity-forms-salesforce/